Re-edited feature version of serial The Phantom Empire (1935). Singer Gene Autry discovers a race of advanced humans living beneath the earth.

Gene Autryas Gene Autry
Frankie Darroas Frankie Baxter
Smiley Burnetteas Oscar (archive footage)
Betsy King Rossas Betsy Baxter
Dorothy Christyas Queen Tika
Wheeler Oakmanas Argo
Charles K. Frenchas Mal
Warner Richmondas Rab
J. Frank Glendonas Prof. Beetson (archive footage)
Edward Peil Sr.as Dr. Cooper (archive footage)